Many prior art roller skates have included mechanical engagement means such as clamping devices for adjusting the width of the wheeled skate, thereby engaging the sides of a skater's article of footwear and securing the wheeled skate thereto. In this regard, a key or wretch was commonly used to adjust a screw or bolt-like drive mechanism. And many prior art roller skates have also included straps and buckles for further securing the chassis of a wheeled skate to a wearer's article of footwear, e.g., U.S. Pat. No. 240,970, U.S. Pat. No. 1,700,058, and U.S. Pat. No. 2,552,987. Some prior art wheeled skates also included length adjusting mechanical means, such as U.S. Pat. No. 1,609,612, and the like, thus permitting a single wheeled skate chassis to accommodate wearers having different size foot lengths. Formerly, it was common for conventional articles of footwear to be used with removable wheeled roller skates.
In recent times, the main trend of the skate industry has been to construct skates having an integral chassis and upper. Accordingly, the relatively rigid integral uppers of many in-line wheeled skates today closely resemble those of ski boots. A few modern wheeled skate uppers can be removed, but most are not intended to be selectively removable. If and when removed from a wheeled skate, these uppers are normally unsuitable to stand alone and serve as a conventional article of footwear. Most of these wheeled skates are of the in-line variety, and the uppers are commonly made of injection molded thermoplastics. The thermoplastic upper normally extends far above the ankle of a wearer. The interior of the upper of many current in-line wheeled skates includes a padded inner liner. The upper and chassis are sometimes molded as a single unit, or alternatively bolted or riveted together. When consisting of a separate component, the chassis portion of the wheeled skate is commonly made of thermoplastics, carbon fiber, or metal such as aluminum, titanium or steel. These types of wheeled skates are often relatively large, awkward, heavy, and expensive. They generally do not breathe well, and as result can be hot and uncomfortable. Wheeled skates of this kind are not easy to transport, and take up considerable space when packing and traveling.
Accordingly, there have been several recent attempts to depart from the use of uppers which generally resemble rigid thermoplastic ski boots in the manufacture of in-line wheeled skates. NIKE, Inc., Canstar Sports Group, Salomon, K-2 Corporation, Hypno, and Rollerblade Inc. have introduced products which have included uppers, that at least in part, more closely resemble conventional athletic shoes. For example, see U.S. Pat. No. 5,331,752 assigned to Rollerblade, U.S. Pat. No. 5,437,466 assigned to K-2 Corporation, and U.S. Pat. No. 5,397,141 assigned to Canstar Sports Group, all of these patents being hereby incorporated by reference herein.
Hypno has made a high top upper which can be selectively attached to a skate chassis, as has Rollerblade, Inc., as disclosed in U.S. Pat. No. 5,331,752. However, these attempts to re-introduce a more conventional and selectively removable shoe upper have not met with great commercial success. One of the reasons is that the would-be shoe uppers have been marginally functional in their dual role as conventional articles of footwear when disengaged from the wheeled skate. However, the present inventor believes that there are other reasons for the commercial failure of these initiatives.
The inventor was raised in Minnesota, and during his lifetime first learned to skate on ice during the wintertime on a generic child's skate characterized by relatively low elevation of the foot, then later on figure skates, hockey skates, and speed skates. Hockey is a major winter sport in Minnesota, and the development of modern in-line skates was largely in response to the need of hockey players to skate and condition themselves in the summer months. And today, nearly the entire in-line skating industry has adopted what is essentially the hockey skate model for their product as concerns skate geometry and skating technique. This is one of the bottlenecks or problems which has stifled the industry. It has prevented consumers, who have no desire to be hockey players or to skate like them, from obtaining more functional skates for the purpose of aerobic exercise, or artistic skating.
The hockey skate is faster, but it is both less maneuverable and less capable of providing high quality skating relative to the figure skate. Many of the maneuvers commonly performed by figure skaters are simply not possible on a hockey skate. The elevation as between the heel of the foot and the ball of the foot is commonly 1¼ inches in a figure skate. The distance between the bottom of the wearer's heel and the supporting ice surface is commonly 2⅝ inches, and the distance between the bottom of the wearer's ball of the foot and the supporting ice surface is commonly between 1⅞ and 2 inches. In contrast, the elevations associated with hockey skates are much higher, that is, commonly 3⅝ inches under the heel, and 2¾ inches under the ball of the foot. As a result of this geometry, the effective leverage and magnitude of the loads which need to be managed about the ankle joint with respect to inversion and eversion of the foot, in particular, by the stabilizing structures of the foot and lower leg such as the peroneals and posterior tibialis, are much greater in the hockey skate, and those skates having like geometry, relative to the figure skate. As result, the configuration of the upper of a hockey skate is normally high, thereby providing support and partial immobilization of the ankle in order to control inversion or eversion of a skater's foot. Figure skates are also characterized by high uppers, but this construction is not required for normal skating on the ice surface, rather this is required to support the ankle and foot regarding the high loads associated with the jumps and gymnastic-like maneuvers that figure skaters commonly perform. No high skate upper is required for normal skating given the common elevation of the heel and ball of the foot consistent with the figure skate model. The loads associated with normal skating maneuvers are generally always less than 2½ body weights, whereas loads in the range between 5-10 body weights can be associated with the jumps commonly performed by figure skaters.
Speed skates for use on ice do not normally include a high upper. The geometry of most speed skates places the ball of the foot higher, and the heel somewhat lower, than that of figure skates. However, in-line speed skates for use on dry land commonly adopt the higher elevations at the ball and heel of the hockey skate model in order to include the use of large wheels which provide for higher speeds when rolling on asphalt. The common practice and need for high and relatively rigid uppers, or other stabilizing devices intended to resist inversion and eversion of the foot in wheeled skates, then largely derives from the adoption of relatively high elevations of the heel and ball of the foot normally associated with the hockey skate model. The relatively high elevation of conventional in-line skates makes skating more difficult for the general public, and likely contributes to many of the falls and injuries which are experienced during in-line skating. Given these considerations, it can be readily understood that much can be said for introducing lower elevations with respect to the heel and ball of the foot in a wheeled skate.
While speed is desired in hockey and speed skates, such is a secondary consideration for those who desire to participate in skating in order to enjoy a non-impact form of aerobic exercise. In fact, the speeds provided by current in-line hockey and speed skates can be unmanageable as concerns safety and braking, in particular, given the presence of hilly terrain or a traffic filled environment. Further, many recreational athletes would be pleased to obtain 30-60 minutes of aerobic exercise each day. Wheeled skates characterized by a skating speed of even 6 minutes per mile would result in 10 miles distance being covered during an hour of exercise. Clearly, slower wheeled skates which might also require a higher aerobic demand could then be suitable for use in aerobic exercise. Today, most wheeled skates are simply too fast to effectively control given the height at which the foot is elevated, the hazards present in an urban or suburban environment, and the lack of truly effective braking systems. The adoption of the hockey skate geometry and model, and focus on attaining high speeds has limited the potential of wheeled skates to meet other criteria with respect to skating, such as the consumer's desire for a non-impact form of aerobic exercise and safety.
A relatively short side stroke is commonly used with a hockey skate, whereas a somewhat longer side stroke is commonly used with a speed skate. Both of these side stroke styles place considerable loads upon the ankle, knee, hip, and lower back of skaters. Accordingly, the side stroke skating style places demands upon a skater which require a high level of conditioning. In truth, the side stroke skating style is more taxing on the anatomy, and more likely to result in injury than the relatively linear stroke technique used in figure skating. The side stroke skating style is also harder to learn and to manage than the linear stroke technique. Walking and running are examples of relatively linear motions with which the general public is most familiar and competent. Accordingly, a wheeled skate built more along the figure skate geometry and model which permits both the use of the linear stroke skating style, and if desired, the side stroke skating style, can be advantageous for use by members of the general public.
The side stroke skating style also requires considerable space in order to execute. On a sidewalk or street, the presence of cars and pedestrians and the danger of collision renders the side stroke style somewhat less safe or manageable. Moreover, the herringbone technique will have to be used when attempting to ascend a hill using a wheeled skate when employing the side stroke skating style, just as when scaling a steep hill using cross-country skis. This technique requires numerous quick side strokes in order to gain elevation, and is both physically taxing and inefficient. In contrast, a wheeled skate which facilitates a linear skating style can enable a skater to ascend a hill with a more direct line of attack.
It is known in the art to include mechanical mating means for properly locating and stabilizing an article of footwear with regards to the chassis of a wheeled skate. For example, “male” members upon the upper surface of a wheeled skate chassis have been used to interact with corresponding “female” grooves or like features in the sole of an article of footwear, as disclosed in U.S. Pat. No. 38,173, and U.S. Pat. No. 5,331,752, or vice-versa, as disclosed in U.S. Pat. No. 2,998,260, U.S. Pat. No. 3,963,251, and possibly wheeled skates made by the Hypno company. The use of mating “male” and “female” members as between an article of footwear and ski is also known in prior art cross-country and downhill ski boot and. binding systems.
It is known to use step-in mechanical engagement means such as the Shimano, Inc. SPD bicycle cleat system with bicycle shoes and petals, and snowboard bindings and boots. The teachings of Shimano, Inc. in this regard include the following U.S. patents: U.S. Pat. No. 5,557,985, U.S. Pat. No. 5,522,282, U.S. Pat. No. 5,505,111, U.S. Pat. No. 5,497,680, U.S. Pat. No. 5,446,977, U.S. Pat. No. 5,205,056, U.S. Pat. No. 5,195,397, U.S. Pat. No. 5,125,173, U.S. Pat. No. 5,115,692, U.S. Pat. No. 5,060,537, U.S. Pat. No. 5,003,841, U.S. Pat. No. 5,778,739, U.S. Pat. No. 5,755,144, U.S. Pat. No. 5,727,429, U.S. Pat. No. 5,363,526, U.S. Pat. No. 5,806,379, U.S. Pat. No. 5,799,957, U.S. Pat. No. 5,784,931, U.S. Pat. No. 5,784,930, U.S. Pat. No. 5,771,757, U.S. Pat. No. 5,699,699, U.S. Pat. No. 5,687,492, U.S. Pat. No. 5,199,324, U.S. Pat. No. 4,622,863, all of these patents being hereby incorporated by reference herein. The teachings of Look, S.A., with respect to step-in bicycle cleat systems includes U.S. Pat. No. 5,787,764, U.S. Pat. No. 5,423,233, U.S. Pat. No. 5,211,076, U.S. Pat. No. 4,893,420, U.S. Pat. No. 4,840,086, U.S. Pat. No. 4,686,867, and U.S. Pat. No. Des. 324,838, all of these patents being hereby incorporated by reference herein. The teachings of Speedplay, Inc. of San Diego, Calif. include U.S. Pat. No. 6,494,117, U.S. Pat. No. 6,425,304, U.S. Pat. No. 5,546,829, U.S. Pat. No. 5,325,738, U.S. Pat. No. 5,213,009, and U.S. Pat. No. 4,942,778, all of these patents being hereby incorporated by reference herein. Other recent patents directed to clipless bicycle systems include U.S. Pat. No. 6,341,540, U.S. Pat. No. 6,276,235, U.S. Pat. No. 6,234,046, U.S. Pat. No. 6,035,743, and U.S. Pat. No. 5,992,266, all of these patents being hereby incorporated by reference herein. However, there appears to be no teaching with respect to the use of a step-in bicycle cleat system in the wheeled skate prior art.
It is known to use aperture plugs with respect to the axles of in-line wheeled skates, e.g., see U.S. Pat. No. 5,048,848 assigned to Rollerblade, Inc. It is also known in the art to provide rocker with respect to an ice skate blade, but also with respect to the geometry of a wheeled skate. And with regards to in-line wheeled skates, it is known to provide adjustable rocker means by providing for movement of one or more of the wheels vertically. In some cases, the front and rear wheels can be moved vertically upwards in order to introduce greater rocker, and in others skates, the middle wheel(s) can be moved vertically downwards to accomplish the same result. U.S. Pat. No. 5,505,470 granted to T. Blaine Hoshizaki and assigned to Canstar Sports Group, hereby incorporated by reference herein, teaches a generally triangular shaped removable insert for quickly making changes to the position of skate wheels in order to adjust the rocker of the wheeled skate as desired. The total amount of rocker introduced in a full sized men's skate is normally less than ½ inch, and more commonly closer to ¼ inch. The desired amount of rocker and adjustment is then normally less than 10 mm, and increments of merely 3 mm are often desirable.
When speaking of in-line wheeled skates, it is not really possible to introduce rocker in a two-wheeled skate, but such is possible with skates having three or more wheels. When rocker is suitably introduced a short distance behind the metatarsal-phalangeal joints associated with the ball of the skater's foot, a three wheeled skate can permit substantially all of the skater's weight and ground contact of the skate to be selectively placed upon the middle wheel. For this reason a three wheeled skate can be advantageous for changing from forward to rearward skating, and vice versa, as well as the conduct of other more demanding skating maneuvers. In an in-line three wheeled skate configuration, both the need for proper rocker in a skate, and the fact that most of the power in the side stroke skating technique during accelerations is transferred from the forward part of the skate, tends to favor placing the middle wheel closer to the front wheel, rather than closer to the rear wheel. In this regard, it can be desirable to change not only the vertical orientation of the middle wheel in order to introduce or fine tune the rocker of the skate, but also to change the horizontal orientation of the middle wheel, that is, to shift the position of the middle wheel towards the toe or heel, as desired, in order enhance the rocker effect.
In a quad wheeled skate, that is, in a four wheeled skate in which the wheels are not positioned in-line, it is normally not possible to perform the so-called hockey-stop braking action unless the skating surface is exceptionally smooth, and/or the frictional characteristics of the wheel and skating surface permit. However, in an in-line two or three wheeled skate the hockey-stop braking action is possible. When braking on a rough surface, the rearmost wheel can then become rapidly abraded. Nevertheless, with respect to side slippage, an in-line two or three wheeled skate behaves much more like a true ice skate, than does a quad wheeled skate. The ability of an in-line three wheeled skate to include rocker and to perform the hockey-stop braking action, thus makes it the closest to a true ice skate as concerns its handling and performance characteristics.
It is known to use roller bearings, ball bearings, but also journal type bearings in wheeled skates, e.g., see German Patent DT 2,507,279 A1, dated Feb. 20, 1975. And it is also known to use thermoplastic bearings with or without lubrication in wheeled vehicles. Manufacturers of suitable thermoplastic bearings include IGLIDE® bearings by IGUS of East Providence, R.I., and NYLINER® bearings by Thompson Industrial Molded Products, Inc. of Port Washington, N.Y. Supplies of resins for such thermoplastic bearings include LUBRICOMP® materials by LNP Engineering Plastics, Inc. of Exton, Pa. and DSM Engineering Plastics of Evansville, Ind. The use of such thermoplastic bearings can reduce bearing weight and cost, and facilitate the design of novel wheel configurations.
Wheeled skates having toe stop or toe drag front brakes are known in the art and such include both roller skates and in-line wheeled skates, e.g., U.S. Pat. No. 5,401,040, U.S. Pat. No. 4,373,736, U.S. Pat. No. 4,392,659, and U.S. Pat. No. 5,372,383. A toe stop or toe drag front brake can serve to check a skater's forward speed when the skater drags the toe of the wheeled skate behind their body upon the skating surface. This action does not so greatly disturb the skater's balance nor result in forces being directed into and thereby disturbing the pelvis as when a skater raises their foot and extending it in front of themselves in order to engage a brake pad that is placed at the rear of a wheeled skate, as is common in some of the in-line wheeled skate prior art. Further, during forward motion the toe stop or toe drag front brake can facilitate turning, thus acting to rotate the torso in the direction of the desired turn much as a bulldozer or tank maneuvers. In addition, when a skater has reversed and is skating rearwards, the toe stop or toe drag front brake can then act de facto as a rear brake, and more substantial braking power can then be generated, that is, relative to a rear mounted brake when the skater is moving forwards. This is due to the fact that the toe stop or toe drag front brake is then more or less directly under the skater's center of gravity and nearly all of the skater's weight can be brought to bear upon the brake without the skater losing balance.
Wheeled skates having fixed brake pads or other braking devices positioned at the rear of a wheeled skate are known in the prior art, e.g., numerous patents granted to David Mitchell including, U.S. Pat. No. 5,664,794, U.S. Pat. No. 5,704,619, U.S. Pat. No. 5,651,556, U.S. Pat. No. 5,649,715, U.S. Pat. No. 5,564,718, U.S. Pat. No. 5,330,207, U.S. Pat. No. 5,211,409, U.S. Pat. No. 5,253,882, and U.S. Pat. No. 5,316,325. Many of these teachings include cuff actuation of a brake pad which is then lowered to engage the skating surface. A skate brake including a rear mounted wheel and brake drum structure is taught in U.S. patents granted to Ed Klukos including U.S. Pat. No. 5,791,663, U.S. Pat. No. 5,630,597, and U.S. Pat. No. 5,511,803. Other rear mounted brake systems include U.S. Pat. No. 5,501,474 assigned to Roces, U.S. Pat. No. 5,415,419 assigned to Canstar Sports Group, U.S. Pat. No. 5,470,085 and U.S. Pat. No. 5,794,950 assigned to K-2 Corporation, U.S. Pat. No. 5,435,579 and U.S. Pat. No. 5,465,984 assigned to Nordica, and U.S. Pat. No. 5,655,783, U.S. Pat. No. 5,299,815 granted to Keller Brosnan.
Most of the existing rear mounted brakes developed for in-line wheeled skates do not develop sufficient braking power to stop a skater moving at speed within a short distance. Further, these rear mounted brake systems do not generally permit the execution of rapid avoidance maneuvers while braking, that is, the act of braking is achieved at the expense of maneuverability. In addition, these rear mounted brakes generally require an erect posture of the skater and leg movements such as straightening the knees to actuate an ankle cuff mechanism, or placing the lower leg and foot well in front of the torso, thus substantially in front of the skater's center of gravity. These actions are not conducive to maintaining balance when stopping suddenly. When skating, the normal reaction of an individual moving forwards when startled and desiring to arrest movement is to crouch and lower the center of gravity, put their hands forward, and to adduct the feet and pronate. Skaters will also dig in their heels, that is, if and when this can be accomplished without losing their balance. These actions are generally consistent with the snow-plow braking methods used in ice skating and skiing. Unfortunately, these actions are generally inconsistent with the posture and movements required to successfully actuate many of the rear positioned brake systems that are presently being used on in-line wheeled skates.
Locating brake pads at either extreme end of an in-line wheeled skate can be counter-productive both from the standpoint of being able to applied substantial forces to the brake pad, and also the skater's need or desire to simultaneously maintain balance, control, and maneuverability while braking. Human anatomy is such that most of the stabilizers of the foot as concerns inversion and eversion, such as the peroneals and posterior tibialis, insert in the midfoot area. The further away that brake pads or similar devices are position from these anatomical stabilizing structures, generally, the greater is the potential leverage and force which can be developed to work against them. This can undermine an in-line skater's ability to brake, balance, and maintain control and maneuverability during hard braking. However, because of the greater stability of a quad wheeled skate, locating brake pads at the front and rear of a quad wheeled skate poses no such problem.
Again, the so-called hockey-stop method can be used to stop an ice skate. Essentially, while moving forwards, a skater turns their skates sideways while applying sufficient force as to more greatly slow the forward part of their skates, then slowly rotates the rear portion of the blade about while dragging the side of the blade across the ice so as to come to a full stop while moving sideways. As stated previously, this maneuver generally cannot be performed with a quad wheeled skate unless the skating surface is smooth and/or characterized by a low coefficient of friction, but it can be performed with in-line two wheeled skates, and in particular, with in-line three wheeled skates. However, this braking maneuver quickly consumes the rear wheel of a skate, as the wheel then effectively doubles as a brake pad. This maneuver is also more difficult and dangerous to perform on dry land given the relative unevenness of most skating surfaces. Moreover, if skaters fall on dry land they will not slide as on ice, and unlike relatively smooth ice, an asphalt skating surface can severely cut and abrade.
There is a need for effective brakes on both in-line and quad wheeled skates, that is, brakes which can safely and quickly stop a skater who is moving rapidly, and without substantially compromising the skater's control and maneuverability. This is believed to be the greatest single issue which prevents in-line and quad wheeled skates from becoming a safe and reliable form of non-impact aerobic exercise. Further, while in-line wheeled skates can provide advantages in speed and maneuverability for a proficient skater, they are not as stable or forgiving for use by the general public as quad wheeled skates. Accordingly, there is a need for an improved quad wheeled skate that would reduce the elevation of a skater's foot, but also increase the width of the wheel base relative to conventional roller skates for the purpose of enhancing stability. Further, there is need for an improved quad wheeled skate that would provide means for employing a relatively linear skating technique. In addition, there is need for a relatively simple, light-weight, and inexpensive suspension for wheeled skates. Moreover, there is need for an improved quad wheeled skate which includes means for rapidly and easily selectively removing an article of footwear that can also be used for one or more activities such as walking, running, and bicycling, and skating, whether in partial or complete combination.